<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
        var a = 10
            b = 20
            console.log(a > b) // flase
            console.log(a < b) // true
            
        var c = 20
            d = 25
            console.log(c >= d) // flase
            console.log(c <= d) // true
            
        var e = '25'
        // == 表示相等 === 表示数据类型和值都相等 
            console.log(e == d) //true
            console.log(e === d) // flase
            
            // 和上面全等一样
        console.log(20 != '20') //flase
        console.log(20 !== '20') // true
        
    </script>
</body>
</html>